A Limonitic Replacement of a Kind of Moss

Abstract

A limonitic substance replacing a kind of moss was found in the floor of astream issuing from a ferruginous spring (pH=2.9) at the Horaitakamatsu mine, Akita Prefecture. The substance is very similar to "limonite" in its external appearance, but the chemical analysis (Table 4) and differential thermal analysis (Fig. 1) show that it is not hydrous ferric oxide but basic ferric sulphat. Its occurrence, microscopic features, chemical analysis, differential thermal analysis, and X-ray diffraction analysis are considered in this paper.